Thermal transients caused by electrical switching devices and fast optical or electrical pulses only exist for a very short time (less than 1 millisecond). If the transient happens in a high thermal conductivity material, e.g. silicon wafer, the thermal transient will disappear in a few milliseconds or faster. Most modern IR cameras have external triggering capability. However, the IR camera often runs on its own clock. If the triggering of data acquisition is not synchronized with the camera, there is often an uncertainty of timing, e.g. 16.7 ms for camera running at 60Hz. Even when the IR camera is running at 500 Hz, there is 2 ms uncertainty. Depending on when you push/click the button, the high-speed thermal transients can be missed and they will disappear in the next image. We developed a technique to synchronize the IR camera to capture the thermal transients. By using a delay function, we can control the data acquisition very precisely to study the thermal transients.